fix(serve): fix slash commands never registering with Discord

Two root causes:
- Commands were added to the tree's global scope but only synced
  per-guild, which uploads an empty list. Added copy_global_to()
  before each guild sync so commands are actually sent to Discord.
- Handler functions used **kwargs, which discord.py can't inspect
  for parameter discovery. Commands like /paw registered without
  their options. Now uses __signature__ injection so discord.py
  sees proper typed parameters.

Also surfaces registration errors via the JSONL error event instead
of silently dropping them into stderr at DEBUG level.

Bumps to v0.5.3.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: DevRohit06

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "discord-cli-agent"
-version = "0.5.2"
+version = "0.5.3"
 description = "Discord CLI for AI agents"
 readme = "README.md"
 license = "MIT"

src/discli/commands/serve.py

@@ -106,7 +106,10 @@ async def on_ready():
         asyncio.create_task(_stdin_reader())
         # Sync slash commands (Discord API call, can take seconds)
         if slash_defs:
-            await _register_slash_commands()
+            try:
+                await _register_slash_commands()
+            except Exception as e:
+                emit({"event": "error", "message": f"Slash command registration failed: {e}"})
 
     @client.event
     async def on_message(message):
@@ -239,54 +242,60 @@ async def on_member_remove(member):
     # ── Slash Commands ──────────────────────────────────────────────
 
     async def _register_slash_commands():
+        import inspect
+
+        _type_map = {"string": str, "integer": int, "number": float, "boolean": bool}
+
+        def _make_slash_callback(param_defs):
+            """Create a callback whose __signature__ exposes params to discord.py."""
+            async def _callback(interaction: discord.Interaction, **kwargs):
+                cmd_name = interaction.command.name
+                itk = str(uuid.uuid4())
+                interactions[itk] = interaction
+                await interaction.response.defer(thinking=True)
+                emit({
+                    "event": "slash_command",
+                    "command": cmd_name,
+                    "args": {k: str(v) for k, v in kwargs.items() if v is not None},
+                    "channel_id": str(interaction.channel_id),
+                    "user": str(interaction.user),
+                    "user_id": str(interaction.user.id),
+                    "guild_id": str(interaction.guild_id) if interaction.guild_id else None,
+                    "interaction_token": itk,
+                })
+
+            # Build a proper signature so discord.py registers slash options
+            sig_params = [
+                inspect.Parameter("interaction", inspect.Parameter.POSITIONAL_OR_KEYWORD,
+                                  annotation=discord.Interaction),
+            ]
+            for p in param_defs:
+                annotation = _type_map.get(p.get("type", "string"), str)
+                required = p.get("required", True)
+                default = inspect.Parameter.empty if required else None
+                sig_params.append(
+                    inspect.Parameter(p["name"], inspect.Parameter.POSITIONAL_OR_KEYWORD,
+                                      annotation=annotation, default=default),
+                )
+            _callback.__signature__ = inspect.Signature(sig_params)
+            return _callback
+
         for cmd_def in slash_defs:
             name = cmd_def["name"]
             desc = cmd_def.get("description", name)
             params = cmd_def.get("params", [])
 
+            callback = _make_slash_callback(params)
             if params:
-                # Command with a single string parameter
-                param = params[0]
-
-                @tree.command(name=name, description=desc)
-                @app_commands.describe(**{param["name"]: param.get("description", param["name"])})
-                async def slash_handler(interaction: discord.Interaction, **kwargs):
-                    cmd_name = interaction.command.name
-                    itk = str(uuid.uuid4())
-                    interactions[itk] = interaction
-                    await interaction.response.defer(thinking=True)
-                    emit({
-                        "event": "slash_command",
-                        "command": cmd_name,
-                        "args": {k: str(v) for k, v in kwargs.items()},
-                        "channel_id": str(interaction.channel_id),
-                        "user": str(interaction.user),
-                        "user_id": str(interaction.user.id),
-                        "guild_id": str(interaction.guild_id) if interaction.guild_id else None,
-                        "interaction_token": itk,
-                    })
-            else:
-                @tree.command(name=name, description=desc)
-                async def slash_handler_no_args(interaction: discord.Interaction):
-                    cmd_name = interaction.command.name
-                    itk = str(uuid.uuid4())
-                    interactions[itk] = interaction
-                    await interaction.response.defer(thinking=True)
-                    emit({
-                        "event": "slash_command",
-                        "command": cmd_name,
-                        "args": {},
-                        "channel_id": str(interaction.channel_id),
-                        "user": str(interaction.user),
-                        "user_id": str(interaction.user.id),
-                        "guild_id": str(interaction.guild_id) if interaction.guild_id else None,
-                        "interaction_token": itk,
-                    })
-
-        # Sync per guild for instant registration (global sync can take hours)
+                descriptions = {p["name"]: p.get("description", p["name"]) for p in params}
+                callback = app_commands.describe(**descriptions)(callback)
+            tree.command(name=name, description=desc)(callback)
+
+        # Copy global commands to each guild for instant availability, then sync
         synced_guilds = 0
         for guild in client.guilds:
             try:
+                tree.copy_global_to(guild=guild)
                 await tree.sync(guild=guild)
                 synced_guilds += 1
             except Exception as e: